The rising global population is inducing a fast increase in the amount of municipal waste and, in turn, issues of rising cost and environmental pollution. Therefore, alternative treatments such as waste-to-energy should be developed in the context of the circular economy. Here, we review the conversion of municipal solid waste into energy using thermochemical methods such as gasification, combustion, pyrolysis and torrefaction. Energy yield depends on operating conditions and feedstock composition. For instance, torrefaction of municipal waste at 200 °C generates a heating value of 33.01 MJ/kg, while the co-pyrolysis of cereals and peanut waste yields a heating value of 31.44 MJ/kg at 540 °C. Gasification at 800 °C shows higher carbon conversion for plastics, of 94.48%, than for waste wood and grass pellets, of 70–75%. Integrating two or more thermochemical treatments is actually gaining high momentum due to higher energy yield. We also review reforming catalysts to enhance dihydrogen production, such as nickel on support materials such as CaTiO3, SrTiO3, BaTiO3, Al2O3, TiO3, MgO, ZrO2. Techno-economic analysis, sensitivity analysis and life cycle assessment are discussed.
相似文献Microplastic pollution has recently been identified as a major issue for the health of ecosystems. Microplastics have typically sizes of less than 5 mm and occur in various forms, such as pellets, fibres, fragments, films, and granules. Mangroves and coral reefs are sensitive and restricted ecosystems that provide free ecological services such as coastal protection, maintaining natural cycles, hotspots of biodiversity and economically valuable goods. However, urbanization and industrial activities have started contaminating even these preserved ecosystems. Here we review sources, occurrence, and toxicity of microplastics in the trophic levels of mangrove and coral reef ecosystems. We present detection methods, such as microscopic identification and spectroscopy. We discuss mitigating measures that prevent the entry of microplastics into the marine environment.
相似文献